Means for mounting electrodes employed in the prevention of corrosion in steam boilers, condensers, and like structures



A. S. GUSH.

MEANS FOR MOUNTING ELECTRODES EMPLOYED IN THE PREVENTION OF CORROSION TN STEAM BOILERS, CONDENSERS. AND L-IKE STRUCTURES. APPLTCATION FILED NOV. 26. 1919.'

1,366,257. Patented Jan. 18, 1921.

2 SHEETS-SHEET I- A. S. GUSH.

MEANS FOR MOUNTING ELECTRODES EMPLOYED IN THE PREVENTION OF CORROSION IN STEAM BOILERS, CONDENSEHS, AND LTKE STRUCTURES.

APPLICATION HLED NOV. 26. 1919.

1,366,257. Patented Jan. 18,1

2 SHEETSSHEET \TTTTL E. -7 f/Z UNITED s'rArss PATENT OFFICE.

ARTHUR S. GUSH. OF EDINBURGH, SCOTLAND.

MEANS FOR MOUNTING ELECTRODES EMPLOYED IN THE PREVENTION OF CORROSION IN STEAM BOILERS, CONDENSERS, AND LIKE STRUCTURES.

Specification of Letters Patent.

Patented Jan. 18, 1921.

Application filed November 26, 1919. Serial No. 340,813.

To all whom it may concern.

Be it known that I, ARTHUR SYDNEY GUsH, engineer, subject of the King of Great Britain, residing at 5 Clifton Terrace, Edinburgh, Scotland, have invented certain new and useful improvements in means for mounting electrodes employed in the prevention of corrosion in steam boilers, condensers, and like structures, of which the following is a specification.

This invention relates to means for mounting electrodes employed in the prevention of corrosion in steam boilers, condensers and like structures, such electrodes projecting into the liquid and being connected with the positive pole of a source of electricity whose negative pole is connected with the structure.

Hitherto it hasbeen customary to support the anode by mounting it on the end of a metal support, or distanm iece extending from and insulated from t e wall of the structure. It has been proposed to insulate the external metallic surface of that portion of the distance piece between the Wall and the anode by completely incasing it in a cover or sleeve of fiber or like strong insulating material. It has been found in actual practice, however, that such fiber covers when submerged in boiler water under boiler steaming conditions become porous, and that if these covers are used in the steam space of a modern boiler thetemperature conditions are sufficiently severe to partially carbonize same. Under both these conditions of use the insulating properties of such covers are destroyed.

Again 'if covers or sleevesare composed of fibrous asbestos for the purpose of overcoming these carbonizing effects, moisture is absorbed by same from condensed steam after boilers have been in use, thereby preventing the use ofsuch an electrolytic system when boilers are cold.

Covers or sleeves have been used constructed of porcelain or similar material of high insulating properties. It has been found that under modern boiler working conditions, covers of such materials cannot be relied on as they are easily broken or fractured and their functions, as eflicient in-. Sula-tors, are thereby destroyed.

By means of my. present invention I have succeeded in producing an insulated distance piece which is free from all the defects above referred to and which does away with the n ecesslty for a separate insulating sleeve. l he insulation on a distance piece manufactured according to my invention does not crack or fracture when used under any conditions normally occurring in condensers or boilers and at the same time retains its insulating properties and exhibits none of the usual disintegrating moisture penetrating effects, produced on insulations previously used or proposed, by the combined temperature and pressure working conditions of a modern high pressure boiler.

. According to this invention I provide an insulating coat which adheres to and for practical purposes becomes an integral part of themetallic distance piece. After many experiments I have found that certain substances are suitable for the purpose of forming this integral insulating coat. Some of these substances are only suitable for use in condensers, where temperature and pressure conditions are not so high as in boilers, and others can be used under any conditions of ordinary practice in either boilers or condensers.

For use under all ordinary working conditions 1 have found that the best class of insulating medium is provided by the phenol formaldehyde condensation products. A coating of one of these. products )referablv mixed with a suitable filler or sti ener, such as asbestos, is molded on the distance piece and stored, the ordinary conditions'of preS- sure and temperature, used in the manufacture of articles with the phenol formaldehydc condensation products being used in these operations.

Satisfactory working results may also be obtained by wrapping the metallic distance pieces with asbestos fabric, previously saturated or impregnated with one of the afore said phenol formaldehyde condensation products, and molding and stoving the distance piece thus wrapped, in the manner previously referred to.

In either case the insulation becomes a practically integral part of the distance piece which is then suitable for use in boilers or condensers under all ordinary conditions in either water or steam space.

If the distance piece is intended for use in a condenser only I have found that a coating of vitreous enamel such as is used in enameled hardware deposited on the metallic distance piece by any ordinary process as used in connection with hardware will provide effective insulation but it should be noted that a distance piece produced by this method will not stand up under the tempera ture and pressure conditions of steam and water in a modern high pressure boiler.

The accompanying drawings show in sectional elevation two forms of distance pieces constructed in accordance with this invention and fitted to the boiler shell. Similar reference letters denote similar parts in both figures.

Referring first to Figure 1, a is a carrier or distance piece of solid steel, circular in cross section and having an end I) of smaller diameter and threaded for about half its length. The other end may be squared as at c and is threaded as at d.

The said carrier is provided in the manner previously described with an integral insulating coating as shown at e.

An electrode f formed with a hole 9 is passed over' the portion a and is secured thereon by means of the nuts h, h. A washer y' separates the electrode f from the coated carrier a. A pad piece I: with an internally'projecting flat surface is riveted at m, m to the curved boiler shell Z and extends through the hole therein. The said pad piece is drilled for the passage of the coated end 6 of the carrier a.

The end I) is passed from inside the boiler through the hole in the pad piece as far as it will go and is secured by means of the nut n. 'lVashers 0 0 of insulatingand suitable jointing material are provided between the end of the pad piece I: and the thicker portion of the carrier a and between the pad piece and the nut n.

The current is supplied to the electrode f as follows Contact is made to the carrier at by fixing the positive supply wire lead 12 over the bare end 6 or stud s and clamping same between the nuts n and g.

The current then flows through the metallic body of the carrier a to the threaded end d or stud t and the nuts 72,, h, and to the electrode 7, by making electric contact between the meeting faces of the electrode 7, and the inner nut 72..

The distance pieces project a suitable distance into the boiler.

Referring now to Fig. 2. The carrier a is for the sake of lightness formed with a hollow bore. This bore is threaded at each end for the reception of studs or bolts 8, t.

u is a bush of insulating material, disposed between the stud s and pad piece k.

In a similar manner and in suitable positions on the boiler other similarly coated bolts ro'ect, commonly known as the peg bolts. These bolts are used for anode supporting purposes only. Thus in boilers the electrodes are entirely supported between these, current supply and peg bolts.

In the circulating water spaces of condensers similarly coated current supply bolts are provided so as to pass through cover or sight hole doors, and have an anode fixed to their internally projecting ends.

With bolts treated in accordance with this invention short circuiting of the current between the anode and the shell of the boiler or condenser through the surrounding liquid is prevented without incasing the distance piece in a separate removable cover or sleeve of insulating material.

By the use of bolts or distance pieces treated in accordance with this invention, no separate porcelain insulators, which when fractured cause short circuiting troubles, as well as possible obstruction of the boiler tubes in water tube boilers, are used, and no separate support bars, riveted or attached direct to the boiler shell are required for supporting my whole system thereby preventing the leakage of positive current to the negative boiler shell which occurs in such systems when the above mentioned porcelain insulators fail.

By t us effectively insulating the said external surfaces of internally projecting portions of current supply or peg bolts and by the abolition of the use of copper strips inside the boiler for current conveying purposes this system is equally serviceable for use when boilers are steaming or filled completely with cold water or filled to working height with cold water.

at I claim is 1. In a boiler, condenser or the like an electrode including a distance piece having an integral insulating coating substantially for the purpose set forth.

2. In a boiler, condenser or the like supporting an electrode by means of a distance piece comprising an integral adhering coating which contains one of the phenol formaldehyde condensation products as an ingredient substantially as and for the purposes described.

3. Supporting an electrode as claimed in claim 2 the coating being formed of one of the phenol formaldehyde condensation products mixed with a suitable filler such as asbestos and applied substantially in the manner described.

4. Supporting an electrode as claimed in claim 2 the coating being formed by wrapping asbestos fabric previously saturated with one of the phenol formaldehyde con- In testimony whereof I have hereunto set densation products around the metallic dismy hand in presence of two subscribing 10 tance piece and treating the same substanwitnesses. tially as and in the manner described.

5. In a condenser an electrode including i a distance piece having an integral adhering \Vitnesses: coat of enamel substantially as and for the NEVILLE E. BRooKEs, purposes described. ERNEST J. HILL.

ARTHUR S. GUSH. 

